Centrifugal fan



G. M. CAPELL CENTRIFUGAL FAN Oct. 16 1923.

Filed Sept; 9, 1922 Patented Get. 13, 1

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' ENGLAND; BY ROBERT 'AL BEDBLA onronnon, ENGLANQAIVDKATELEEN MA IE DAVIES; 'coivrmoNL CAL ENGLAND, LEGAL REPRESENTATIVES:

CENTRIFUGALFANJ i Bejit known that, GEORGE Gareth,"

7 deceased, suhjectoffthe King of GreatBrit-c ain, lateresiding at Passenhain, near Stony Stratford, in the county of Bucks, England,

has invented new and, useful Iinp'rove nents inv Centrifugal F which following specification.

This jinvention relates to centrifugal fans and development of "the invention de j :scribed in the specificationsfof G M. CaQ pells "prior Patent "No. 991134; and patent ,Lwhereby; an

application Serial No. 4L98095 increased efficiency is obtainech In these "prior inventions f certainfn' ain vanes curved in the direction of rotation are described, each followed by a; tail blade,

curvedcont'rary t'othefdir'e'ction of rotation and leavingafdivergent spacehto which air has accessl 'in' the fan of 991134 from the front or back of the main vane through a passage provided by what is therein termed a porthole covered byabent away portion of the main vane or tailblade; and inthe' a fan of 498095 is described following intermediate vane ma be arranged to cause impelled air to irnpingeuponthe rear sur; face of the tailblade and asjsistgthe rotation a fanptests ofv which have proved to have a greater efliciency thaneither of the above The main vane, curved in the direction of rotation and extending into the area of the eye or inlet circle, whereit may be pro vided with a scoop wing, is followedjby'a. tail blade curved contraryfto the direction of rotation, to the divergent space between a I i divergenttherefrom, being curved in the di which tail blade and main vane air flows by a passage leading. from the front of the main'vane, and behind the tail blade islo-' cated an intermediate short vane'curved 1n 4 the direction ofrotationextendingfrom the" V tween same whereby any tendency to the periphery partway to the eye ofthe fain Theintermediate vane is of oppositely directed curvature to that of the tail blade 7 situated in advance thereof. .Thisvintermej diate vane, byithe convergence of itsputer I end towards the outer end of the tail blade,

pro-vides a constriction in the passage-bee Now according to the present inventiom of the fan wheel.

E'D'CAPEL'L; or sr;inawannenfrsrjn-or WI fiip n titnniea September 9, 1922; "swam;i587,129.-jf

I forl nationiof a t-the; of the wheel behind the tail b-lade ;is*ba1-;

anced by the plenum of fluid delivered by nt r di he n m t' coepip rt nb Y in g" set back -.re'latively to S the direction of rotation and relatively to and overlapping the. more outward portions thereof, so that the scoop portion of the main vane delivers: y Y

a1rto impinge] against the back of. the tail Z blade. Alsoeachfinterinediate vane niay be duplicated with their inner borders progres: sively remoter ,from thefeye of the fanp Two examples of centrifugal fan wheejls according tothe present invention: are illustrated on the accompany ng 1 drawing in which tion, and; c

Fig, 2 isa{transverse. sectionfof one-eX-j;

k I w side elevation, partly 'ngsed .tionlofathe otherrexaniplel The direction of rotation is shownby'the arrows.

mple; vF 9 3. i a

Referring more particularly to Figs. 1

blade 6, springing from the back thereof and I rection contrary to the rotation andextendins: to the periphery of the wheel. ,a

Each main vane c ;0 @is interrupted by" a; passage fpermitt-ingjthe flow Of-liIfIOIli the front of .the innerportion 0 of themain vane to thedivergent space between the Figflisja side elevation, perta n secprovided within the 7 eye 6 with scoop wings cl.

e5 H and 2: a a aretheside plates and b theieye I v Extending between thej 'side'plates a 'and;fron1 the periphery of Each main vane a} c isbacked a tail 2 outer portion thereof andits cfollowing tail blade e;

Behind each tailblade e is an internie'diate vane 9, curved in the direction of rotation, and extending" from the periphery-- of the 105, wheel partway to the -eye' by -Thii1iter1 J I niediate this 9 supplies a plenum" of air at the peripheryoi the 1 wheel to the back 7 eonst i -et i nfshowe in Figlof the respeetivetail blade 6 which balances f V any tendency to the formation of ELVaCUIUTI at the-J ha k f the 1 mil lade which wo d Se 15 9a Per pher l of air:

froniithat showndn Figs. landQ in so Y 'far as each main Vane 1s divlded, an innermost portion 0* bearing the scoop wing iZ being. set back and overlapping the more outward "portions c andfThis inner- I HOSt -PQIUOIL C? of the malnyvane del vers i d -1y to; inp e sa ns h b c t er p et r 'ta-ilfbl 1 v v Also eaehintermediate vane is dupli; cated," there being two intermediate vanes o1 whieh t he inner border of the more iearwardlyg is "re-meter fromithe eye :7 "indieated 'by dot dash lines w in Fig. 2(

Q be 'proyide'dhnstead of one in the fan ac cording to Fig-*1 moreover such plurality may, both in the fan according "to Fig.

Apluralityof intermediate vanes g may 3 as' well as in the fan according to I;

.exeeed two, 'intern e diatewanes. A ;We"cla1-n1:-'

tation extending from the periphery into -1 -;.--In' -a*'oentrifugal fan, an aperturedj main vanecurved in the direction of re s the eyeofsaid fan; a tail blade curved con trary to the direction of rotation extending from theperiphery and contacting with said n1ain"yane and located behind the 'a oer-,v .tureinsaid main vane, and aninterlmediate sliortyane curvedin'. the directionof rot-a blade.

3 differ towards the eye of said fan behind said tail 2. In a centrifugal, fan, an apertured main vane in two portions curved in the direetion of rotation one portion extending from the periphery into. the eye of said fan and the other portion set back behind said first portion and extending into the eye of saidJfan, a tail blade curved, contrary to the direction of rotation extending from the periphery and contacting with said first portion of said main vane and located behind the aperture in said; main'vane, and an in ter'inediate shortyane ,curvedf in the direc- 'tion of rotation extending from the peripheryipartway towards the eye of said fai behind sa d il b a e- In' a centrifugal; fan; an apertured main vane in two portions curved in the direction of rotation one portion exte d ingfrom the periphery into the, eye of; said a 7 fan and the other portion set back behind said first portion and extending into thefeye of said fame-tail blade curved, contrary to the direction of rotation extending from s the periphery and contacting with said first portion of said main'fvane'and located betion extending from the perphery partway hind the aperture in. Said main vane, and a plurality of intermediate short vanes, curved 'inthe direction of, rotation. extending trom the periphery progressi'yely less partway towards the eye of saidfan behind said tail blade. I

' In testimony whereof we hare signed our names to this specification.

' ROBERT ALFRED. BLAKE,

KATHLEEN MARIE DAV VE'S,

(Common-lyoalledCareer), ZegaZ Rpra' sentatioesi of George ll faoje Uapell ale;

ceased, o 

